Remove ON DELETE CASCADE

metacat-common-server/src/main/java/com/netflix/metacat/common/server/connectors/exception/ConnectorException.java

@@ -50,7 +50,7 @@ public ConnectorException(final String message, @Nullable final Throwable cause)
      *
      * @param message            message
      * @param cause              cause
-     * @param enableSuppression  eable suppression
+     * @param enableSuppression  enable suppression
      * @param writableStackTrace stacktrace
      */
     public ConnectorException(

metacat-common-server/src/main/java/com/netflix/metacat/common/server/connectors/exception/DatabasePreconditionFailedException.java

@@ -0,0 +1,48 @@
+package com.netflix.metacat.common.server.connectors.exception;
+
+/*
+ *
+ *  Copyright 2024 Netflix, Inc.
+ *
+ *     Licensed under the Apache License, Version 2.0 (the "License");
+ *     you may not use this file except in compliance with the License.
+ *     You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *     Unless required by applicable law or agreed to in writing, software
+ *     distributed under the License is distributed on an "AS IS" BASIS,
+ *     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *     See the License for the specific language governing permissions and
+ *     limitations under the License.
+ *
+ */
+
+import com.netflix.metacat.common.QualifiedName;
+import lombok.Getter;
+
+import javax.annotation.Nullable;
+
+/**
+ * Exception when database can't be deleted because ON DELETE CASCADE is
+ * disabled and a table still exists in the database.
+ *
+ * @author gtret
+ */
+@Getter
+public class DatabasePreconditionFailedException extends ConnectorException {
+    /**
+     * Constructor.
+     *
+     * @param name                      qualified name of the database
+     * @param message                   error description
+     * @param error                     stacktrace
+     */
+    public DatabasePreconditionFailedException(final QualifiedName name,
+                                               @Nullable final String message,
+                                               @Nullable final Throwable error) {
+        super(String.format("Precondition failed to update table %s. %s", name, message), error);
+    }
+}
+
+

metacat-connector-polaris/src/functionalTest/resources/schema.sql

@@ -25,5 +25,5 @@ create table TBLS (
   created_date TIMESTAMP not null,
   last_updated_by STRING(255),
   last_updated_date TIMESTAMP not null,
-  foreign key (db_name) references DBS(name) ON DELETE CASCADE ON UPDATE CASCADE
+  foreign key (db_name) references DBS(name) ON DELETE RESTRICT ON UPDATE CASCADE
 );

metacat-connector-polaris/src/main/java/com/netflix/metacat/connector/polaris/PolarisConnectorDatabaseService.java

@@ -10,6 +10,7 @@
 import com.netflix.metacat.common.server.connectors.exception.ConnectorException;
 import com.netflix.metacat.common.server.connectors.exception.DatabaseAlreadyExistsException;
 import com.netflix.metacat.common.server.connectors.exception.DatabaseNotFoundException;
+import com.netflix.metacat.common.server.connectors.exception.DatabasePreconditionFailedException;
 import com.netflix.metacat.common.server.connectors.exception.InvalidMetaException;
 import com.netflix.metacat.common.server.connectors.model.DatabaseInfo;
 import com.netflix.metacat.connector.polaris.common.PolarisUtils;
@@ -87,6 +88,13 @@ public void delete(final ConnectorRequestContext context, final QualifiedName na
         try {
             this.polarisStoreService.deleteDatabase(name.getDatabaseName());
         } catch (DataIntegrityViolationException exception) {
+            if (exception.getCause() instanceof org.hibernate.exception.ConstraintViolationException) {
+                throw new DatabasePreconditionFailedException(
+                    name,
+                    String.format("Cannot delete database %s because it is not empty.", name.getDatabaseName()),
+                    exception
+                );
+            }
             throw new InvalidMetaException(name, exception);
         } catch (Exception exception) {
             throw new ConnectorException(

metacat-connector-polaris/src/test/java/com/netflix/metacat/connector/polaris/PolarisConnectorDatabaseServiceTest.java

@@ -1,4 +1,3 @@
-
 package com.netflix.metacat.connector.polaris;
 
 import com.google.common.collect.Maps;
@@ -167,4 +166,3 @@ public void testDeleteDb() {
         Assert.assertFalse(polarisDBService.exists(requestContext, DB1_QUALIFIED_NAME));
     }
 }
-

metacat-connector-polaris/src/test/java/com/netflix/metacat/connector/polaris/store/PolarisStoreConnectorTest.java

@@ -19,6 +19,7 @@
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.boot.test.mock.mockito.SpyBean;
 import org.springframework.dao.DataAccessException;
+import org.springframework.dao.DataIntegrityViolationException;
 import org.springframework.dao.OptimisticLockingFailureException;
 import org.springframework.data.auditing.AuditingHandler;
 import org.springframework.data.auditing.DateTimeProvider;
@@ -182,6 +183,24 @@ public void testTableCreationAndDeletionWithParams() {
         Assert.assertFalse(polarisConnector.tableExistsById(tblEntity.getTblId()));
     }
 
+    /**
+     * Test database deletion if table exists and ON DELETE CASCADE is disabled.
+     */
+    @Test
+    public void testDbDeletionNoCascade() {
+        final String dbName = generateDatabaseName();
+        final String tblName = generateTableName();
+        final PolarisDatabaseEntity dbEntity = createDB(dbName);
+        final PolarisTableEntity tblEntity = createTable(dbName, tblName);
+
+        Assert.assertTrue(polarisConnector.databaseExists(dbName));
+        Assert.assertTrue(polarisConnector.tableExists(dbName, tblName));
+        Assertions.assertThrows(DataIntegrityViolationException.class, () ->
+            polarisConnector.deleteDatabase(dbName));
+        Assert.assertTrue(polarisConnector.databaseExists(dbName));
+        Assert.assertTrue(polarisConnector.tableExists(dbName, tblName));
+    }
+
     /**
      * Test to verify that table name can be updated.
      */

metacat-connector-polaris/src/test/resources/h2db/schema.sql

@@ -25,7 +25,7 @@ create table TBLS (
   created_date TIMESTAMP not null,
   last_updated_by varchar(255),
   last_updated_date TIMESTAMP not null,
-  foreign key (db_name) references DBS(name) ON DELETE CASCADE ON UPDATE CASCADE
+  foreign key (db_name) references DBS(name) ON DELETE RESTRICT ON UPDATE CASCADE
 );
 
 CREATE INDEX DB_NAME_IDX ON TBLS(db_name);

metacat-functional-tests/metacat-test-cluster/datastores/crdb/sql/schema.sql

@@ -25,5 +25,5 @@ create table TBLS (
     last_updated_by STRING(255),
     last_updated_date TIMESTAMP not null,
     constraint uniq_name unique(db_name, tbl_name),
-    foreign key (db_name) references DBS(name) ON DELETE CASCADE ON UPDATE CASCADE
+    foreign key (db_name) references DBS(name) ON DELETE RESTRICT ON UPDATE CASCADE
 );